Saved in:
Bibliographic Details
Main Authors: Chen, Yanzhe, Ma, Kevin Yuchen, Lv, Qi, Lin, Yiqi, Bai, Zechen, Gao, Chen, Shou, Mike Zheng
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2605.07381
Tags: Add Tag
No Tags, Be the first to tag this record!
Table of Contents:
  • While Vision-Language-Action (VLA) models offer broad general capabilities, deploying them on specific hardware requires real-world adaptation to bridge the embodiment gap. Since robot demonstrations are costly, this adaptation must often occur under a strict data budget. In this work, we identify a critical diversity trap: the standard heuristic of "maximizing coverage" by collecting diverse, single-shot demonstrations can be self-defeating due to non-vanishing estimation noise. We formalize this phenomenon as a Coverage--Density Trade-off. By decomposing the policy error into estimation (density) and extrapolation (coverage) terms, we characterize an interior optimal allocation of unique conditions for a fixed budget. Guided by this analysis, we propose Anchor-Centric Adaptation (ACA), a two-stage framework that first stabilizes a policy skeleton through repeated demonstrations at core anchors, then selectively expands coverage to high-risk boundaries via teacher-forced error mining and constrained residual updates. Real-robot experiments validate our trade-off framework and demonstrate that ACA significantly improves task reliability and success rates over standard diverse sampling strategies under the same budget.